1. Field of the Invention
The invention relates generally to an automatic animal watering system, and more particularly, relates to an automatic animal watering system providing a controlled volume of drinking water to animal cages. The invention additionally relates to a method of operating such a system.
2. Discussion of the Related Art
Providing drinking water to caged animals, particularly in laboratories and other facilities having hundreds or thousands of cages, faces many unique challenges that are not otherwise confronted when watering animals. Due to the complexity and size of modern facilities, large populations of test animals are often required. These test animals typically include small mammals such as mice or rats, but may also include larger test animals. Isolating one or more test animals in a confined cage is often required to prevent comingling of the entire test population and to control experimental variables. To conserve space as well as to provide easy access and visual inspection, these cages are often stored in elongated rows, which are stacked upon one another to form a rack of cages. The individual cages within the rack must each be supplied with water for test animal drinking.
Drinking water is supplied to the caged animals via animal-operated drinking valves. The typical drinking valve includes a stem that dispenses water when the stem is deflected by an animal. The valves may receive water from bottles or bags located within the cage or via manifolds that receive water from a central source of an integrated automated watering system. Manifolds typically are preferred in larger facilities because the monitoring and refilling of individual bottles is time consuming, particularly with large test populations.
However, automated water systems, like any closed system, are susceptible to forming leaks. Any such leak may result in the flooding of one or more cages on a rack at the risk of the well-being of the animal or animals housed therein and potentially jeopardizing the associated research.
Additionally, as these conventional automated water systems combine individual drinking valves with a plumbing system connected to a single high-volume water source, there is often no mechanism for isolating the water supply, and attendant risk of leaks, to less than all of the cages mounted on a particular rack. It is likewise impossible to determine where such a leak is located within the rack. This concern is particularly significant in situations in which the volume of water supplied to each individual drinking valve must be limited due to 1) a desire to minimize the potential harm by reducing leakage at any location to a set volume, 2) the constraints of a given experiment requiring limited water distribution to each cage, and/or 3) a desire to determine the rate of water consumption per cage. Prior systems also typically were incapable of monitoring water flow to individual cages or rows of cages without employing other monitors, such as flow meters or cameras, hence reducing the capability of such systems to monitor and control the water supply to individual cages or rows of cages.
Thus, despite prior attempts to design an automatic animal water system, there remains need for improvement.
For example, there is a need to mitigate the potential harmful effects of a leak at a given rack or a given location on a rack by quickly identifying and isolating the location of the leak while maintaining water supply to at least part of the remainder of the racks or remainder of locations on an individual rack.
There is also a need to permit monitoring and control of the volume of water supplied to individual cages or to at least an easily monitorable group of cages, such as the cages on one row of a rack, or even supplied to a rack.